<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <meta http-equiv="X-UA-Compatible" content="ie=edge" />
  <title>学生信息管理</title>
  <link rel="stylesheet" href="css/index.css" />
</head>

<body>
  <h1>新增学员</h1>
  <form class="info" autocomplete="off">
    姓名：<input type="text" class="uname" name="uname" />
    年龄：<input type="text" class="age" name="age" />
    性别:
    <select name="gender" class="gender">
      <option value="男">男</option>
      <option value="女">女</option>
    </select>
    薪资：<input type="text" class="salary" name="salary" />
    就业城市：<select name="city" class="city">
      <option value="北京">北京</option>
      <option value="上海">上海</option>
      <option value="广州">广州</option>
      <option value="深圳">深圳</option>
      <option value="曹县">曹县</option>
    </select>
    <button class="add">录入</button>
  </form>

  <h1>就业榜</h1>
  <table>
    <thead>
      <tr>
        <th>学号</th>
        <th>姓名</th>
        <th>年龄</th>
        <th>性别</th>
        <th>薪资</th>
        <th>就业城市</th>
        <th>操作</th>
      </tr>
    </thead>
    <tbody>
      <!-- 
        <tr>
          <td>1001</td>
          <td>欧阳霸天</td>
          <td>19</td>
          <td>男</td>
          <td>15000</td>
          <td>上海</td>
          <td>
            <a href="javascript:">删除</a>
          </td>
        </tr> 
        -->
    </tbody>
  </table>
  <script>
  // 参考数据
      const initData = [
        {
          stuId: 1001,
          uname: '欧阳霸天',
          age: 19,
          gender: '男',
          salary: '20000',
          city: '上海',
        }
      ] 
         const tbody = document.querySelector('tbody');
         const renderData = JSON.parse( localStorage.getItem('info')) || [
       {
          stuId: 1001,
          uname: '欧阳霸天',
          age: 19,
          gender: '男',
          salary: '20000',
          city: '上海',
        }
       ]
       // 开始渲染
       function render(data){
       const trArr= renderData.map(function(item,index){
            const tr = `
            <tr>
          <td>${item.stuId}</td>
          <td>${item.uname}</td>
          <td>${item.age}</td>
          <td>${item.gender}</td>
          <td>${item.salary}</td>
          <td>${item.city}</td>
          <td>
            <a href="javascript:" data-id="${index}">删除</a>
          </td>
        </tr> `
            return tr
       })
          tbody.innerHTML = trArr.join('')
       }
       render(renderData)
      // 录入数据
      const info = document.querySelector('.info')
      const items = info.querySelectorAll('[name]') 
      info.addEventListener('submit',function(e){
          e.preventDefault()
          for(let i = 0; i<items.length; i++){
            if (items[i].value ==='') return  alert('内容不能为空')
          }
           const obj = {
            stuId: renderData[renderData.length-1]?.stuId+1 || 1,
          uname: items[0].value,
          age: items[1].value,
          gender: items[2].value,
          salary: items[3].value,
          city: items[4].value,
           }
           renderData.push(obj)
          render(renderData)
          localStorage.setItem('info',JSON.stringify(renderData))
          this.reset()
      })
      // 删除数据
      tbody.addEventListener('click', function (e) {
            if(e.target.tagName ==='A'){
               const index = e.target.dataset.id 
               renderData.splice(index,1)
               localStorage.setItem('info',JSON.stringify(renderData))
               render(renderData)

            }
      });

  </script>
</body>

</html>